Sellier and Bellot powder?

I've been given 10kg of powder that has been stripped from sellier and bellot 8x57 JS 196 grain ammo. I wish to reload this in my .308.....So anybody know which powder they use?
If it helps, it is of the grey flaked variety and not extruded granules. Any help much appreciated.

There is really no way to know outside of a lab what the burn rate of that powder is. Ammo makers do not use canister powders like we can get. They get powder tons at a time made up to their specific pressure and velocity standard. It would be a shot in the dark, but if you knew what the average charge of that powder was when it was in the 8mm ammo and what velocity it was pushing the bullet you could look for loads that would use the same grains of powder to push the same weight bullet the same velocity and it might give you a ball park idea of what the burn rate is. Fooling with powder of unknown burn rate can get you into trouble very quickly. I would ask myself. Self, is saving a few $$ worth maybe blowing up my rifle and me? My answer is NO WAY.